Forward / Rewind buttons

I have created forward and rewind buttons to draw on the info bar.  In
addition, I have created seek_sec() to seek the song by X seconds.
Right now, the seek buttons add +/- 5 seconds to the current position.

libsaria/music/__init__.py

@@ -60,6 +60,18 @@ def seek(prcnt):
 	return call("SEEK", audio.seek, prcnt)
 
 
+def seek_sec(sec):
+	global audio
+	dur = audio.duration()
+	if dur > 0:
+		prcnt = get_progress() + (1 * sec * 1000000000) / audio.duration()
+		if prcnt > 1:
+			prcnt = 1
+		if prcnt < 0:
+			prcnt = 0
+		seek(prcnt)
+
+
 def get_progress():
 	global audio
 	dur = audio.duration()

ocarina/button.py

@@ -62,6 +62,20 @@ class NextButton(Button):
 	def clicked(self, button):
 		LS.collection.plist_next()
 
+
+class ForwardButton(Button):
+	def __init__(self):
+		Button.__init__(self, gtk.STOCK_MEDIA_FORWARD)
+	def clicked(self, button):
+		LS.music.seek_sec(5)
+
+
+class RewindButton(Button):
+	def __init__(self):
+		Button.__init__(self, gtk.STOCK_MEDIA_REWIND)
+	def clicked(self, button):
+		LS.music.seek_sec(-5)
+
 class OpenButton(Button):
 	def __init__(self):
 		Button.__init__(self, gtk.STOCK_OPEN)

ocarina/info.py

@@ -59,9 +59,11 @@ class InfoBar(Bar):
 		self.pack(self.title, True, True)
 		self.pack(label.TimeLabel())
 		self.pack(label.LengthLabel2())
+		self.pack(button.RewindButton())
 		self.pack(button.PlayButton())
 		self.pack(button.PauseButton())
 		self.pack(button.StopButton())
+		self.pack(button.ForwardButton())
 		self.pack(button.NextButton())
 		self.pack(button.UpButton(up_button))